I recently stumbled over a problem on my notebook running Ubuntu 16.04 “Xenial Xerus”. When trying to connect to a new, protected Wi-Fi network no password dialogue appeared, making a quick GUI connection impossible. Creating the connection manually, entering the Wi-Fi password in the “Wi-Fi-Security” setting in the process worked like a charm. Using nmtui from the terminal also worked flawlessly.

As I didn’t connect the notebook to new Wi-Fi networks in months, I didn’t encounter this error for a long time. Therefore I had a lot of problems debugging it as I installed bazillions of updates and new packages in the meantime.

I narrowed the problem down to NetworkManager not having a way of saving the Wi-Fi password, which is normally done via gnome-keyring, specifically via gnome-keyring-daemon. The daemon didn’t seem to start properly, but even starting it manually still didn’t make a difference. The logs still complained:

Finally I found the solution in an askubuntu question. Nearly half a year ago I installed Flatpak so I could install FeedReader. One of the dependencies was dbus-user-session. This package seems to have problems with the gnome-keyring-daemon in 16.04 rendering it defective. Purging the dbus-user-session package and its dependencies solved my problem and the Wi-Fi password dialogue appeared once again.

apt purge dbus-user-session xdg-desktop-portal xdg-desktop-portal-gtk

I still had a problem with the NetworkManager applet in the tray, but this could be fixed with an apt install --reinstall network-manager-gnome and a reboot afterwards.

Nearly two months ago I published my OpenSSL scribblings post. This one is the spiritual successor, addressing Java Keystore handling this time. There are already a lot of good web sites on how to handle the keytool, so I will limit myself to the issues I encounter from time to time which are more difficult to figure out. Similar to the last post I will use COMODO as CA and ssl.example.org as domain.

Adding a new certificate to a keystore

Requirements:

The full certificate chain

The certificate itself

The certificate private key

First concatenate the cert chain if not already in one file. A Comodo speciality is the occasional inclusion of Windows line breaks, so we use sed for output to substitute any occurence of these. Additionally we ensure that the certificate starts on a newline:

I’m currently running a couple of tests with Docker swarm mode on Scaleway. For those who don’t know Scaleway, it’s a PaaS provider which is part of online.net. Due to capped maximum prices per month and no Ingress/egress prices it’s good for smaller projects.

But small prices often also mean a couple of limitations as well. In my case I wasn’t able to run Docker swarm mode properly. I tried running a stack with a couple of web servers and Traefik as Reverse Proxy, but for some reason this didn’t work. When running a Traefik container manually in Docker, everything worked fine. But as soon as I tried using it in swarm mode context, there was no connectivity. Dockers logs showed some strange errors similar to these: